Urchin-like iron oxide and a method for producing the urchin-like iron oxide

Abstract

The present invention relates to an urchin-like iron oxide and a method for producing the urchin-like iron oxide. The urchin-like iron oxide comprises a core and multiple needle-like elongations protruded from the core. The needle-like elongations could be wire, rod, tube, cone, and flake. The length/width ratio of the needle-like elongation is high enough to apply in an optoelectronic field. The method in accordance with the present invention is to stably heat an iron-contained powder under room temperature by a thermal oxidation. The surface of the iron-contained powder is slow oxidized to form an urchin-like iron oxide with multiple uniform distributed needle-like elongations protruded from the surface. The size of each needle-like elongation is easily adjusted and changed by controlling the heating temperature. The method has advantages of simplified operation and lowered expense.

1 . An urchin-like iron oxide, comprising:
 a core, being an iron powder and have a surface; and   multiple needle-like elongations, being radically and radiated mounted on the surface of the iron core and having a top portion protruded form the surface and a connected portion mounted and conjugated on the surface of the core.   
     
     
         2 . The needle-like elongations as claimed in  claim 1 , wherein the needle-like elongations are wire, rod, tube, cone, or flake. 
     
     
         3 . The urchin-like iron oxide as claimed in  claim 1 , wherein each needle-like elongation being at least 50 nanometers in length. 
     
     
         4 . The urchin-like iron oxide as claimed in  claim 3 , wherein the top portion of each needle-like elongation being at least 5 nanometers in diameter. 
     
     
         5 . The urchin-like iron oxide as claimed in  claim 4 , wherein the connected portion having a bottom is at least 30 nanometers in width. 
     
     
         6 . A method for producing an urchin-like iron oxide comprising steps as following:
 providing a raw material: providing a grinded iron-contained powder; and   heating and oxidation: putting the iron-contained powder on a plate and heating the iron-contained powder by a stable temperature for a period.   
     
     
         7 . The method for producing an urchin-like iron oxide as claimed in  claim 6 , wherein the temperature being at least 220° C. 
     
     
         8 . The method for producing an urchin-like iron oxide as claimed in  claim 7 , wherein the heating step form room temperature to the stable temperature being increased by 1 to 20° C. per minute. 
     
     
         9 . The method for producing an urchin-like iron oxide as claimed in  claim 8 , wherein the iron-contained powder being heated for at least half hour. 
     
     
         10 . The method for producing an urchin-like iron oxide as claimed in  claim 9 , wherein the heating and oxidation step having a oxidation rate by an oxide is increased 0.2 to 1.5 wt %. 
     
     
         11 . The method for producing an urchin-like iron oxide as claimed in  claim 10 , wherein the heating and oxidation step being operated under an atmosphere condition or an oxygen concentration by at least 10 mole percentages.